Agitator muller



June 10, 1941- A. c. CHRISTENSEN m-AL 4, 5-

AGITATOR MULLER Filed June 22; 1939 s Sheets-Shet 1' ALFRED C.CHRI3TEN$EN, Lg I BARNEY CnsToR,

June 1 1941- A. c. CHRISTENSEN :rm. 2,244,765

AGITATOR MULLER Filed June 22, 1939 s Sheets-Sheet 2 Jwvm ALFRED 6' CHRISTENSEN, BARNEY CASTOR,

June 1941' A. c. CHRISTENSEN ETAL ,765

AGITATOR MULLER Filed June 22, 19:59 s Sheets -She'e t s EH35. 1E5. A I? I99 .51 v 22 31 \a/ s G 19 9/ Q I Q Q,

other.

Patented June 10, 1941 12,244,765 AGITATOR MULLER Alfred C. Christensen and Barney Castor, Chicago, Ill., assignors to Herbert S. Simpson, 'Ohi- V cage, 111.

Application June 12%, I939, Serial No. 280,605

2 Claims.

This invention relates to a mixer which is particularly adapted to be used in the intensive mixing of two or more materials with one an- The device of the present invention is adapted to be used in the chemical field generally andwherever a plurality of ingredients, some of which are solid, are to be intensively admixed with one another. It is especially useful for mixing dry or semi-plastic materials, such as used in the ceramic industry and elsewhere.

The principal object of the present invention is to provide an intensive mixer wherein the mixing is accomplished by one or more mixing blades which ,move in an orbital path about the center of the mixing device, and, at the same time, are positively rotated in their orbital path.

Another object is to provide a mixer of the foregoing type wherein the mixing blades are rotated in their orbital path in such a direction that maximum eflicien-cy of mixing is attained,

Still another object is to provide a mixer of thejforegoing type which utilizes the pan and drivingmeans of a wheel type muller and which is, therefore, adapted to be manufactured by the application of the features of the present invention to existing type mullers.

Another object is to provide a mixer of the type referred to above wherein the rotation of the mixing blades, as they are revolved in their orbital pathabout the center of the mixing pan, is effected by positive driving means; in the preferred embodiment, this driving means comprises a stationary circular member disposed with its driving edge concentric with the orbital path of the mixing blades, and means for rotatably driving the mixing blades, as they are revolved in their orbital path, from this stationary driving member.

, Yet another object stationary sprocket concentric withthe mixing pan, a driven sprocket on the axis of and connected with the shaft of the mixing blade, and a sprocket chain encircling the stationary sprocket and the driven sprocket whereby the revolution of the blade causes it to be driven rot-atably and positively by the sprocket chain.

Still another object is to provide driving means for rotating the mixing blade a plurality of times for each revolution thereof about the center of the device; in this way, the intensity of the mixing is greatly enhanced.

Yet another object is to provide in a mixer of the foregoing type one or more scrapers which is to provide driving me'ans for the mixing blades which comprises a engage the sides of the muller pan and throw scraped material inwardly into the path of the mixing blades.

Still another object is to provide one or more plows which engage a central stationary turret located at the center of the mixing pan and which are adapted to throw scraped material outwardly into the path of the mixing blades.

While the invention will be described as employing a plurality of orbitally revolved mixing blades, it will be understood that only one such mixing blade may be employed although this will considerably reduce the speed of the mixing.

gear stationary broken away, so as to more clearly illustrate the remaining parts.

Figure 3 is a plan view showing a modified form of drive iorthe agitating blades.

. Figure 4. is a vertical section taken through the .tiu'ret and driving mechanism of the modification shown in Figures 1 and 2.

Figure 5 is a schematic view of the drive of Figures 1 and 2.

Figure 6 is a schematic view of a modified form of construction.

Figure '7 is a schematic view of a still further modified construction, wherein the agitating blades are rotated .at difierent speeds.

Figure 8 is a schematic view of a still further modification, in which friction gears or spur gears are utilized instead of a sprocketch-ain or friction belt, to drive the agitating blades.

Referring to the. drawings in detail, reference numeral. I designates generally a muller pan having a supporting casting which is lined with a wear-resisting pan bottom ,3, and is provided at its edge with a circular pan wall 4. A main drive shaftS is supported beneath the muller pan I and drives through enmeshing gears 6 and 1.

Gear 1 is keyed to a vertical shaft 8 which extends upwardly throughv casting ,2 and which is lo- Shaft 8 extends up through a turret 9 and is keyed above turret 9 to the revolving cross head designated generally as l0.

Cross head ID carriesat its opposite ends blade supporting castings H which are detachably secured thereto. These castings II are provided with rotatable vertical blade-carrying shafts I2 which are journaled in journals I3 mounted on castings II. Any suitable means is provided to prevent vertical displacement of rotating shafts I2, as for example, suitable thrust bearings in journals I3 or collars I4 fixedly mounted upon shaft I2 exteriorly of journals I3. Shafts I2 carry the agitating blade assembly, designated generally as II, which comprises a cross member I5 and, depending therefrom, a plurality of spaced blades I6. As indicated in the drawings, these blades are preferably spaced away from. the center of shaft I2 and symmetrically at equal distances therefrom, although obviously any desired spacing of blades I6 along member I5 may be employed. Blades I6 may be unsymmetrically and unevenly disposed if desired. Preferably these blades I5 extend downwardly to a point where they almost but do not quite touch the upper surface of wear plate 3, as is clearly indicated in Figure 1. If desired, suitable means (not shown) may be provided for adjusting the tips of the blades I5 vertically with respect to plate 3.

As a result of the construction thus far described, as drive shaft 5 is rotated, vertical shaft 8 is similarly rotated together with accompanying cross head IE. Consequently, blade-carrying shaft I2 and the blade assembly II carried thereby revolve in a circular orbit about the center of the mixing pan. 7

Means is provided for causing rotation of the blade assembly I1 about its own axis as it is revolved about the center of the mixing pan. This means may comprise a stationary sprocket I8 for each of the shafts I2. Shafts I2 have fixedly attached to their upper ends relatively small sprockets I9 whiohmesh with a sprocket chain 2!! which encircles and meshes with relatively large sprocket I8.

Any suitable means is provided for holding central sprockets IB stationary as blade assemblies IT are revolved in their orbital paths. In the form of theinvention shown in Figures 1. 2 and 4, this means comprises a cross member 2! fixedly attached-to and supported by supports 38 attached to the upper portion of the wall 4. Cross member 2I has its central axis on a diameter of the mixing pan. Bolts 22 extend downwardly from cross member 2I through sprockets I8, thereby holding said sprockets stationary. Sprockets I8 are iournaled freely about an extension 23 which extends upwardly from shaft-8 andis integral therewith. Thus, shaft 8 and extension 23 are, free to rotate relative to stationary sprockets I8. A thrust Washer 24 rotatably supports-the weight of sprockets I8 upon a nut 39 which is tightly locked upon the upperthreaded portion .40 of shaft 8. A sealing washer 25 is fixedly mounted on the upper end of extension 23 and keeps material being mixed or being supplied to the mixer from access to the bearing of sprockets I8 onextension 23 or upon thrust -.washer 24. V

In the modified form of drive shown in Figure 3, a concentric circular friction driving rim .26 is stationarily supported by and inwardly of wall 6 of the mixing pan by supports 31 which are fixedly mountedadjacent the upper'rim of wall 4. A friction driving member 2'! is keyed to blade-carrying shaft I2 and frictionally engages driving rim 25 sothat as blade-carrying shaft I2 is revolved about the center of the mixing pan, friction gear Z'Icausesrotation of shaft I2 in the desired direction and at the desired speed. .In

this modification, preferably resilient means such 75 as spring 28 is interposed between cross head I0 and friction gear 21 so as to yieldingly urge friction gear 21 into driving engagement with driving track 26. In order to accomplish this, the blade supporting casting may be made into two parts, Ila and Nb, casting Ilb being slidably mounted relative to casting I la. by means of slots 29 provided therein cooperating with pins 30 fixedly mounted in casting Ila and spring 28 being so disposed that it urges casting Ilb outwardly with respect to casting Ha and cross head I0.

Instead of using afriction gear and driving rim in the modification of Figure 3, gear 21 might be a toothed gear cooperating with a toothed circular stationary rack.

As indicated, blade-carrying shaft I2 is rotated more than once per revolution of driving shaft 8 and cross head ID. This is accomplished by having sprocket I9 formed with fewer teeth thansprocket I8. In a preferred form, shaft I2 will rotate 4 or more times per revolution of cross head III. In the modification of Figure 3, a similar ratio is provided. In Figures 5 to 8, there are illustrated schematically, various methods of carrying out the inventive thought. Figure 5 i1- lustratesschematically the form of the invention embodied in Figures 1, 2 and 4 wherein two separate stationary sprockets I8 drive two separate planetary sprockets I9 by means of two separate sprocket chains 20.

In Figure 6, the result accomplished is the same'as that of Figure 5 but with a simplification of the assembly, only one stationary sprocket I8 being employed, and a common sprocket chain 20a driving both planetary sprockets I9 at the same speed of rotating.

In Figure '7 differential rotation of the blade assemblies isobtained, stationary sprocket IBa being of smaller diameter than sprocket I8b whereby planetary sprocket I 911 is driven at lower speed than sprocket I92); so that the blade assembly driven by sprocket I911 rotatesat alower speed than that drivenby sprocket I911. .It is to be understood that instead of using sprockets and sprocket chains in Figures 5 to 7, suitable friction pulleys and friction belt may be employed. Figures 5 to 7 have been purposely drawn to illustrate either friction or toothed driving means.

a In Figure 8, an alternative form of construction is shown wherein a stationary sun gear IBc drives planetary gears I90 in the desired direction throughthe intermediary of idler gears 3|.

Idler gears 3I revolve with cross head II) and therefore, with the blade-carrying assemblies. Gears-fl may be fixedly attached to a shaft M which is rotatably mounted on casting -I I. The gears may be either friction gears or toothed gears, of any suitable type. Thus the blade assemblies are rotated at the same speed and. in the same directionas in the modification shown inFigures 1 and 2.

Scrapers 32 and 33 carried by arms fixedly attached to cross ,head I!) scrape the sides and outer bottom portion of muller pan I, throwing the scraped material inwardly into the path of the revolving and rotating blade assemblies I1. A plow134, mounted at the lower end ofa vertical arm 42 mounted oncross head I5, revolves about turret 9 and scrapes the same by means of beveled edge 43 provided at the innermost portion of its enlarged end 44. Plow 34 also scrapes the inward bottom portion of muller pan I and throws the scraped material outwardly into the path of blade assemblies IT. The agitator assemblies l1 throw materials being mixed onto the outer periphery of the stationary muller pan I, that is, onto the wall 4 and the outer peripheral portion of the bottom 3. The scraper 32 carries the material from the outer periphery of the muller pan in front of one of the agitator assemblies l1. Plow 34 creates an outward movement of the material, cooperating with scraper 32 to mix the material, and this mixing effect is greatly accentuated by the mixing assemblies H, the path of which overlaps that of the delivery ends of scraper 32 and plow 34, and which rotate and revolve at relatively high speed. Scraper 33 scrapes material inwardly into the path of plow 34 which moves it. slightly outwardly into the path of the other of the agitator assemblies l1. Although scraper 33 greatly increases the mixing efliciency of the machine, it may be omitted if desired. Since the leading portion of the agitator assemblies, which first encounters the material, moves outwardly towards the side wall, the agitators tend to throw more material outwardly than inwardly, the trailing portion of the agitator encountering what is left and throwing it inwardly toward the turret. Thus, a continued transfer of the material to and from the side wall from and to the mixing blades, and to and from the turret from and to the mixing blades is effected while mixing the material intensively by reason of the combined rotation and revolution of the agitators.

The cross head l and the blade-carrying shafts l2 are revolved in the direction indicated by the arrows A. At the same time, the blade assembly I! is rotatedin the direction indicated by the arrows B. The result is that the leading portions of the blade assembly I! throw the material outwardly, while the trailing portions throw the material inwardly towards the turret 9. This has been found to give more efficient and more intensive mixing than would be obtained were the blade assemblies rotated in the opposite direction. However, it is to be understood that either direction of rotation is within the spirit of our invention in its broader aspect.

A door 35 is provided in the bottom of the muller pan I. This door is normally mounted flush with the bottom of the muller pan so as to not interfere with the mixing and with the action of the scrapers and plow. Any suitable means (not shown) may be provided for opening this door downwardly to allow discharge of the mixed material through the opening thus formed.

As shown in Figures 1 and 4, the cross head III is provided with a downwardly extending skirt 36 which surrounds the upper portion of turret 9 and prevents material being mixed from obtaining access to the drive shaft 8 and its bearings.

blade assemblies I1 and scrapers 32 and 33 and plow 34 with respect to pan I, the parts named may be held stationary and pan 1 rotated, thereby imparting the same relative orbital or revolving motion between the parts, and the same rotation of agitator assemblies ll about their own axes. Or both pan l and cross head Hi and the parts carried thereby may be rotated with respect to each other although this may involve objectionable drive complications.

It is to be understood that we intend to include as within our invention such modifications as may be necessary to adapt the same to varying conditions and uses and as fall within the terms or the spirit of the appended claims.

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is:

1. In a mixer, in combination, a mixing pan, two spaced independent mixing assemblies therein, means for causing each of said mixing assemblies to revolve in an orbital path, each of said mixing assemblies having an axis of rotation and comprising a plurality of aligned longitudinally spaced mixing rods disposed on both sides of said axis, said rods depending to a point adjacent the bottom of said mixing pan and their depending portion being free, a scraper engaging said pan and a plow engaging said pan bottom discharging into the orbital path of travel of said mixing assemblies, and means for rotating said mixing assemblies about their own axes at different speeds as they revolve in said orbital paths. 2. In a mixer, a mixing pan, a driving shaft disposed centrally thereof and projecting upwardly therethrough, a stationary turret extending vertically from said pan upwardly around said driving shaft, a cross head fixedly attached to said shaft and disposed upon said turret, an individual mixing assembly suspended from each end of said cross head upon a rotational axis and provided with gear means for driving said assembly, said shaft projecting above said cross head, a stationary gear journaled upon the nor:- tion of said shaft which projects above said cross head and supported above said cross head, a flexible driving means located above said cross head and drivingly connecting said mixing assembly gear to said stationary gear so that said mixing assembly is rotated about its own axis as it is orbitally revolved by said shaft, and means above said stationary gear for retaining said gear stationary with respect to said driving shaft.

ALFRED C. CHRISTENSEN. BARNEY CASTOR.

Instead of revolving cross arm l0, carrying- 

